Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A032357
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A032357 Convolution of Catalan numbers and powers of -1. +0
5
1, 0, 2, 3, 11, 31, 101, 328, 1102, 3760, 13036, 45750, 162262, 580638, 2093802, 7601043, 27756627, 101888163, 375750537, 1391512653, 5172607767, 19293659253, 72188904387, 270870709263, 1019033438061, 3842912963391, 14524440108761 (list; graph; listen)
OFFSET

0,3

COMMENT

Absolute value of the alternating sum of Catalan Numbers. - Alexander Adamchuk (alex(AT)kolmogorov.com), Jul 03 2006

Sums of two consecutive terms are A032357[n-1]+A032357[n]=1,2,5,14,42..=A000108[n] Catalan Numbers. The prime p divides a((p-3)/2) for p=11,19,29,31,41,59,61,71..=A045468[n] Primes congruent to {1, 4} mod 5. Prime p divides a(2p+1) for p=5,11,19,29,31,41,59,61,71..=A038872[n] Primes congruent to {0, 1, 4} mod 5. Also odd primes where 5 is a square mod p. - Alexander Adamchuk (alex(AT)kolmogorov.com), Jul 03 2006

Hankel transform is F(2n+1). - Paul Barry (pbarry(AT)wit.ie), Jul 22 2008

Equals INVERTi transform of A000958 [From Gary W. Adamson (qntmpkt(AT)yahoo.com), Apr 10 2009]

Inverse binomial transform of A002212 . [From Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Sep 17 2009]

FORMULA

G.f.: c(x)/(1+x), where c(x) = g.f. for Catalan numbers.

Sum((-1)^(n-k)*C(k), k=0..n), C(k)=A00108(k), Catalan numbers

a(n)=((-1)^(n+1)-binomial(2*(n+1), n+1)*sum((-5)^k*binomial(n+1, k)/binomial(2*k, k), k=0..n+1))/2

Also: a(n)=C[2n, n]/(n+1)-a(n-1)=A000108[n]-a(n-1) with a(0)=1. - Labos E. (labos(AT)ana.hu), Apr 26 2003

a(n) = Sum[ (-1)^(k+n)*CatalanNumber[k], {k,0,n}]. - Alexander Adamchuk (alex(AT)kolmogorov.com), Jul 03 2006

MATHEMATICA

Table[Sum[(-1)^(k+n)*CatalanNumber[k], {k, 0, n}], {n, 0, 60}] - Alexander Adamchuk (alex(AT)kolmogorov.com), Jul 03 2006

CROSSREFS

Cf. A000108.

Cf. A000108, A014137, A014138, A033297, A045468, A038872, A064739.

A000958 [From Gary W. Adamson (qntmpkt(AT)yahoo.com), Apr 10 2009]

Adjacent sequences: A032354 A032355 A032356 this_sequence A032358 A032359 A032360

Sequence in context: A038987 A142957 A080155 this_sequence A144056 A062630 A159458

KEYWORD

easy,nonn

AUTHOR

Wolfdieter Lang (wolfdieter.lang(AT)physik.uni-karlsruhe.de)

EXTENSIONS

More terms from Christian G. Bower (bowerc(AT)usa.net), Apr 15 1998.

More terms from Alexander Adamchuk (alex(AT)kolmogorov.com), Jul 03 2006

page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified November 9 12:23 EST 2009. Contains 166233 sequences.


AT&T Labs Research